This invention relates to an acoustic device for custom installation, i.e., an acoustic device enabling listeners to enjoy music in plural zones such as rooms in a house and, more particularly, to such device in which switching on and off of loudspeakers by listeners has been facilitated.
A custom installation of acoustic devices has been increasingly adopted in some countries, particularly in U.S.A., and several systems for custom installation have been developed. It is generally an aim of the custom installation to enable a listener to listen to music in all rooms of his house and, for this aim, devices such as an amplifier and a CD player which require a power supply are installed only in a main room (a guest room is generally used as the main room) and in-wall loudspeakers and operation panel or receiver unit for an infrared remote controller are installed in each of plural sub-rooms.
FIG. 2 shows the simplest form of such prior art system in which music can be enjoyed in a main room 10 and a single sub-room 12. In the main room 10, there are installed a receiver 14 (an acoustic device consisting of a combination of an audio amplifier and a tuner) adapted for use for plural rooms and loudspeakers 16 and 17. In the sub-room 12, there are installed loudspeakers 18 and 19 and an infrared receiver 20. As receiver terminals of the receiver 14, terminals of system A and terminals of system B are provided. The loudspeakers 16 and 17 of the main room 10 are connected to the loudspeaker terminals of the system A of the receiver 14 through cables 30 and 31 and the loudspeakers 18 and 19 of the sub-room 12 are connected to the loudspeaker terminals of the system B of the receiver 14 through cables 32 and 33. In the main room 10, an infrared command signal 23 from a remote controller 23 is received by an infrared receiving section 24 of the receiver 14. In the sub-room 12, an infrared command signal 28 from a remote controller 26 is received by the infrared receiver unit 20 and applied to a received signal input terminal of the receiver 14 through a cable 34.
A key for commanding switching on and off of each of the systems A and B is provided in a corresponding one of the remote controllers 22 and 26. When switching on of the system A is commanded, the loudspeakers 16 and 17 of the main room 10 are turned on whereas when switching on of the system B is commanded, the loudspeakers 18 and 19 of the sub-room 12 are turned on. When switching on of both the systems A and B is commanded, the loudspeakers 16-19 of the rooms 10 and 12 are all turned on so that one can listen to music in the respective rooms.
FIG. 3 shows another example of the prior art systems which utilizes two power amplifiers connected to two different sources. In the main room 35, two power amplifiers 36(A) and 37(B) are provided. A CD player 38 is connected to the power amplifier 36 and a tuner 40 is connected to the power amplifier 37. The outputs of the power amplifiers 36 and 37 are set to a proper constant tone volume. In the main room 35, there are also provided loudspeakers 39 and 41 and an operation panel 42. The operation panel 42 includes a changeover switch 44 for switching between the outputs of the power amplifiers 36 and 37 and an attenuator 46 for adjusting tone volume. There are first and second sub-rooms 48 and 50. In the first sub-room 48, loudspeakers 52 and 54 and an operation panel 56 are provided and in the second sub-room 50, loudspeakers 58 and 60 and an operation panel 62 are provided. The operation panels 56 and 62 are constructed in the same manner as the operation panel 42 in the main room 35. The outputs of the power amplifiers 36 and 37 are supplied commonly to the operation panels 42, 56 and 62 and from these panels to the loudspeakers 39, 41, 52, 54, 58 and 60. According to this device, by manual operation of the operation panels 42, 56 and 62, either one of the outputs of the power amplifiers 36(A) and 37(B) can be selected independently for each of the rooms 35, 48 and 50 and a listener can listen to the selected music at a selected tone volume.
FIG. 4 shows another prior art in which an infrared re-transmitter called "repeater" is employed. In a main room 64, there are provided a receiver 66, loudspeakers 68 and 70, a loudspeaker on/off switch 72, a repeater receiving section 74 and a repeater re-transmitter section 76. In a first sub-room 78, there are provided loudspeakers 80 and 82, a loudspeaker on/off switch 84 and a repeater receiving section 86. In a second sub-room 88, there are provided loudspeakers 90 and 92, a loudspeaker on-off switch 94 and a repeater receiving section 96. By operating remote controllers 98, 100 and 102 from the respective rooms, infrared signals are received by the repeater receiving sections 74, 86 and 96. The received signals are collected to the repeater re-transmitting section 76 of the main room 64 and re-transmitted therefrom. The re-transmitted infrared signal is received by the receiving section 104 of the receiver 66 whereby the receiver 66 can be operated from the respective rooms 64, 78 and 88.
In the system of FIG. 2, turning on and off of the loudspeakers for each of the rooms 10 and 12 can be made by a remote control operation in each room 10 or 12. Since, however, this switching operation must be made for each channel, a listener must know which channel is assigned to his room. If he erroneously makes an operation of a wrong channel, loudspeakers of a wrong room will be turned on or off. Probability of such erroneous operation is particularly high in a case where there are acoustic devices located in many rooms (i.e., channels). Moreover, in this system, operation keys of respective channels must be provided on each remote controller so that each remote controller must have a large number of keys.
In the system of FIG. 3, turning on and off of the loudspeakers of the respective rooms 35, 48 and 50 must be made by a manual operation of the attenuator 46 in the operation panels 42, 56 and 62 provided in the respective rooms. This is inconvenient because switching of these loudspeakers by a remote controller cannot be made.
In the system of FIG. 4, as in the system of FIG. 3, turning on and off of the loudspeakers in the rooms 64, 78 and 88 must be made by a manual operation of the loudspeaker on/off switches 72, 84 and 94 provided in the respective rooms 64, 78 and 88. This is also inconvenient because switching by a remote controller cannot be made.
It is, therefore, a first object of the invention to provide an acoustic system capable of enabling a listener to enjoy music in plural rooms which has overcome the above described disadvantages of the prior art systems by enabling a listener to turn on and off loudspeakers of his room accurately by a very simple operation of a remote controller.
FIG. 8 shows another example of prior art acoustic devices for custom installation. The system of FIG. 8 is one applied to a house having a main room 310 and four sub-rooms 311-314. In the main room 310, there are provided, as an acoustic device main unit 16, a receiver 318 (a combination of a tuner and an amplifier), an automatic changer type CD player 320, a cassette tape recorder 322, a video tape recorder 324 and, if necessary, power amplifiers 326 and 328. There are also provided loudspeakers 330 and 332 and an infrared receiving unit 334. An acoustic signal from the acoustic device main unit 316 is supplied from an acoustic signal line 350 to the loudspeakers 330 and 332 through the infrared receiving unit 334. The infrared receiving unit 334 includes a photo-diode and receives an infrared command signal 338 (a signal for performing various operations in the acoustic device main unit 316) from an infrared transmitter 336 (remote controller) and transmits it through a command signal line 340. In the infrared receiving unit 334, there is provided a loudspeaker relay so as to turn on and off the loudspeakers in the main room 310 by the system on/off command from the infrared transmitter 336.
In the first through fourth sub-rooms 311-314, there are provided loudspeakers 330 and 332 and infrared receiving units 334 and an acoustic signal from the acoustic device main unit 316 is supplied through acoustic signal lines 351-354. A command signal from the infrared transmitter 336 received by the infrared receiving units 334 in the respective sub-rooms 311-314 is transmitted to the main room 310 through command signal lines 351-354.
A command signal input/output unit 356 is provided in the main room 310. This unit 356 receives command signals from the rooms 310-314 transmitted through the command signal lines 340-344, combines all of these command signals and outputs a combined signal. This combined signal is supplied to re-transmitting LEDs 361-364 through a command signal line 360 for re-transmission. The re-transmitted signal is received by respective infrared receiving sections of the acoustic devices 318, 320, 322 and 324 for execution of the command.
According to the system of FIG. 8, the acoustic device main unit 316 can be controlled freely from the rooms 310-314 by using the infrared transmitter 336 but it is not possible in this system to simultaneously listen to different sources in different rooms.
As a system which has improved this problem and is enabling listeners to simultaneously listen to different sources in different rooms, there is a prior art system shown in FIG. 9. In this system, receivers 318-0 to 318-4 are provided in an acoustic device main unit 316, each receiver being used exclusively for a corresponding one of plural rooms. Received signals (command signals) from the respective rooms are supplied independently to re-transmission LEDs 361-0 to 361-4 for re-transmission and the re-transmitted signal is received by the exclusive receivers 318-0 to 318-4 for an individual control. A command signal input/output unit 356 combines command signals from the respective rooms by means of an adder 366 and supplies a combined output to the re-transmitting LEDs 362-364 through a command signal line 368 for re-transmission. The re-transmitted signals are received by source devices 320, 322 and 324 whereby these source devices are controlled from the respective rooms. For preventing receiving of a re-transmitted infrared command signal by an acoustic device other than an object device, the re-transmission LEDs 361-0 to 361-4 and 362 to 364 are attached directly on the receiving sections of the respective acoustic devices.
According to the system of FIG. 9 in which an exclusive receiver is provided for each room, listeners can simultaneously listen to different sources in different rooms, for example, a CD player 362 in the main room 310, a cassette tape recorder 363 in the first sub-room 311 and a video tape recorder 364 in the second sub-room 312.
In the system of FIG. 9, listeners can simultaneously listen to different sources in different rooms but they cannot simultaneously listen to the same kind of source in different rooms, e.g., simultaneously listen to different Compact Discs. If two CD players are provided, it is of course possible to simultaneously listen to different Compact Discs in two different rooms but, even in this case, there sometimes arises inconvenience. Let it be assumed that there is provided a CD player for exclusive use of parents in addition to a CD player which can be used commonly by all members of a family including two children. Since each source device can be controlled commonly from each room, there arises a case in which the two children use the two CD players simultaneously and the parents cannot use their own CD player.
Aside from this problem, there is a demand for an arrangement according to which a particular device can be controlled from a particular room only (e.g., the video tape recorder can be controlled only from the main room and the parents' room). In the system of FIG. 9, however, the source devices 320, 322 and 324 can be controlled commonly from all rooms and, accordingly, it is not possible to satisfy such demand.
It is, therefore, a second object of the invention to provide an acoustic device capable of limiting a controllable zone depending upon the situation of use of the respective acoustic devices whereby the acoustic device can be more conveniently used.